#!/bin/sh
# user name...
# echo "Please enter your 1:"
# read 1

if [[ -n "$1" ]]; then
  if [ "$1" -lt 20 ] || [ "$1" -ge 50 ]; then
        echo "Sorry, you are out of the [20,50] range."
  elif [ "$1" -ge 20 ] && [ "$1" -lt 30 ]; then
        echo "You are in your 20s"
  else
        echo "You are older than 30s"
  fi
else
   echo "A number is needed as argument"
fi

